Organic Chemistry MCQ question and answer with solution | Chemistry Gk MCQs

A 'battery' (specifically, a traditional lead-acid car battery) uses a chemical reaction to produce electricity.
Sulphuric acid acts as the electrolyte in this battery.
The electrolyte allows the flow of electrical charge between the electrodes (lead and lead dioxide).
Ethylene glycol is antifreeze, used in car radiators to prevent freezing, not batteries.
Sodium bicarbonate is baking soda, commonly used as a cleaning agent or antacid.
Ethanol is a type of alcohol, sometimes used as a fuel or solvent.
So, sulphuric acid is the key chemical found in traditional batteries for conducting electricity.

The correct answer is Option B: oxygen.

Let's understand why:

1. Ethine is also commonly known as Acetylene (C2H2). It is a gas that burns very easily and releases a lot of heat.
2. For welding, we need an extremely hot flame to melt and join metals. To make Ethine (Acetylene) burn with such high intensity, it needs to be mixed with pure oxygen.
3. This process is called Oxy-acetylene welding. When Ethine burns in pure oxygen, it produces a flame that can reach temperatures over 3000°C! This incredible heat is what makes it suitable for cutting and welding metals.
4. Using pure oxygen provides a much hotter and more concentrated flame compared to burning Ethine in just air, because air only contains about 21% oxygen (the rest is mostly nitrogen, which doesn't help with burning).

Let's see why the other options are not correct:

* Option A: ethanol is an alcohol. While it burns, it does not produce the extremely high temperatures required for industrial welding of metals.
* Option C: carbon dioxide is a gas that is often used to put out fires (like in fire extinguishers), not to make them burn hotter or support combustion.
* Option D: air contains oxygen, but also a lot of nitrogen and other gases. Burning Ethine with air would create a flame, but it wouldn't be nearly as hot or efficient for welding as a flame created with pure oxygen.

The general formula for alkanes is C_nH_{2n + 2}.

Alkanes are the simplest type of hydrocarbons and are also known as saturated hydrocarbons.

In this formula, "n" represents the number of carbon atoms in the molecule.

The formula indicates that for every "n" carbon atoms, there are "2n + 2" hydrogen atoms.

This formula applies to all alkanes, regardless of the number of carbon atoms present in the molecule.